Back Mechanics Presented by QBE Loss Control Services

Back Injuries Statistics 25% of low back injuries account for 95% of costs of low back injuries NIOSH- 70% of general public will have back pain in their lifetime 80% of back pain caused by inadequate exercise Back injuries account for 25% of all WC claims and 33-44% of all WC costs

Spinal Column

The spine is made up of 33 vertebrae. The upper 24 vertebrae are separated by a jelly filled layered ligaments called disks. These disks act as shock absorbers for the spine. The facet joints are the back part of the vertebrae that form the channel for the spine. The lumbar region are the five large vertebra composing the lower back, allowing the back to bend forward and back.

Spinal Column

Discs and Force

Herniated Discs

Lower Spine

Spine Range of Motion

Back Mechanics

Danger Zones

Anatomy of Proper Lifting

If you are out of physical shape can also result in increased loads when we improperly lift.

Balance of Forces

Without Weight ? lb x 2 in = (65 lb x 9 in) + (15 lb x 15 in) + (25 lb x 24 in) ? X 2 in = 1410 lbs Force on Back = 705 lbs TorsoArmsHead

Balance of Forces With Weight ? lb x 2 in = (65 lb x 9 in) + (15 lb x 15 in) + (25 lb x 24 in) +(20 lb x 36 in) ? X 2in = 2130 lbs Force on Back = 1065 lbs TorsoArmsHeadObject

Equivalent Forces

Relative Disk Pressure

Relative Disk Pressure Sitting Posture